JPH1012988A - Circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make any processes for performing the borings, platings and solder-fillings of through holes after laminating wiring circuits on both surfaces of an insulation board unnecessary, by punching two metallic plates to form the circuit boards having required wiring circuits and holes, and by interposing an insulation board between the two metallic circuit boards having the wiring circuits and cylindrical protruding portions, and further, by fitting the protruding portions into the holes to integrate the metallic and insulation boards with each other. SOLUTION: In metallic plates 1A, 1B, wiring circuits are machined by punching and pressing, etc. To taking electric continuities between the two wiring circuits when disposing the metallic plates 1A, 1B on both surfaces of an insulation board 2. both through holes 3A, 3B and cylindrical protruding portions 4A, 4B formed respectively in the peripheries of the through holes 3A, 3B are machined by drawing in the pressing processes. Then, into the hole 3A of the protruding portion 4A, the other protruding portion 4B is fitted. The metallic plates 1A, 1B are so buried in the insulation board 2 that the heights of their surfaces are made equal respectively to the heights of the front and rear surfaces of the insulation board 2. Thereby, any processes for performing the borings, platings and solder-fillings of through holes after laminating wiring circuits on both the surfaces of an insulation board can be made unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board used for various electronic devices, particularly, a power circuit such as a power supply circuit.

[0002]

2. Description of the Related Art Two metal substrates formed by punching a metal plate to form a required wiring circuit (circuit pattern) are prepared, and an insulating support (insulating substrate) is interposed between the metal substrates. As a circuit board, for example, Japanese Utility Model 7-20937
Has been proposed.

FIG. 9 is an exploded perspective view of a main part of the construction concept, and FIG. 10 is a perspective view of a cross section of the main part of the through hole part in FIG.
9 and 10, reference numerals 5A and 5B denote metal plates,
Reference numeral 6 denotes an insulating support (insulating substrate), 7 denotes an electronic component, 8 denotes a plating layer, and 9 denotes a solder.

A conventional circuit board is provided on both sides of an insulating substrate 6.
The metal plate 5A and the metal plate 5B punched into a required circuit pattern are embedded and integrated such that their surfaces are substantially the same as the surface of the insulating substrate 6.

In order to make the wiring circuits arranged on both sides of the insulating substrate 6 mutually conductive, a through hole 10 is opened in a portion where the wiring circuit is made conductive, a plating layer 8 is provided on the inner surface, and solder 9 is filled.

The above-mentioned conventional circuit board can be manufactured by the following method. First, the two metal plates 5A and 5B punched into a required wiring circuit are aligned with each other at a portion where a through hole is to be formed.
Metal plate 5A and metal plate 5B on both sides
A circuit board can be manufactured by pouring into the gap and integrally molding.

Further, a metal plate 5A and a metal plate 5B each having a printed wiring circuit are laminated on both surfaces of a prepreg sheet constituting the insulating support 6. This is heated and pressed by a hot press to soften the prepreg sheet. In the process of further curing, the metal plate 5A and the metal plate 5
By embedding B to the vicinity of the surface, a circuit board is completed.

Thereafter, in order to make the wiring circuits on both sides conductive, a hole 10 is made in a portion where the electrical connection is made, and a plating layer 8 is formed on the inner surface.
Is provided, and the solder 9 is filled.

[0009]

However, in the above-mentioned conventional circuit board, it is necessary to accurately position the wiring circuits on both sides in order to make the wiring circuits on both sides conductive. Then, after being integrated with the insulating substrate, holes, plating, and a step of filling with solder are required, resulting in an increase in cost.

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-cost circuit board by a simple structure and a simple process, which eliminates the need for holes after plating, plating, and filling with solder.

[0011]

In order to solve the above-mentioned problems, a circuit board according to the present invention comprises: (1) a circuit board provided with required wiring circuits and holes by punching a metal plate; An insulating substrate (arbitrary insulator member) is interposed between a required wiring circuit and a circuit board provided with a cylindrical protrusion, and the hole and the protrusion are fitted and integrated. (Claim 1).

(2) An insulating substrate is interposed between a metal plate and two circuit boards provided with a required wiring circuit and a cylindrical protrusion, and the protrusions are fitted to each other to be integrated. (Claim 3)

(3) Between a metal plate punched out of a metal plate and provided with a required wiring circuit and a cylindrical projection, and a circuit board punched out of the metal plate and provided with a required wiring circuit and a projection. The circuit board is characterized in that the cylindrical projection and the projection are fitted and integrated with an insulating board interposed therebetween (claim 7).

(4) Between a metal plate punched out of a metal plate and provided with a required wiring circuit and a cylindrical projection, and a circuit board punched out of the metal plate and provided with a required wiring circuit and a projection A circuit board is characterized in that the insulating board is interposed, and the hole and the end face provided on the projection and the bulging portion are fitted and integrated so as to come into contact at three places (claim 12).

According to the present invention, it is possible to obtain a low-cost circuit board with a simple structure and process, which eliminates the need for holes after lamination, plating, and filling with solder.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a circuit board in which a required wiring circuit and a hole are provided by punching a metal plate, and a required wiring circuit is formed by punching a metal plate. An insulating substrate is interposed between the circuit board and the circuit board provided with the projecting portion, and the hole and the projecting portion are fitted together to form a circuit board. The opening step, the plating step, and the soldering step become unnecessary, and the number of steps and cost can be reduced.

According to a second aspect of the present invention, at least one of the metal plates is embedded in the insulating substrate so as to be substantially flush with the surface of the insulating substrate.
According to the circuit board described above, the integrated strength of the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

According to a third aspect of the present invention, an insulating substrate is interposed between a circuit board provided with a required wiring circuit and a cylindrical protrusion by punching a metal plate, and And a circuit board characterized by being integrated by being fitted therein, so that a hole making step, a plating step, and a soldering step are not required, and the number of steps and cost can be reduced.

According to a fourth aspect of the present invention, at least one of the metal plates is embedded in the insulating substrate such that the surface of the metal plate is substantially flush with the surface of the insulating substrate.
According to the circuit board described above, the integrated strength of the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

According to a fifth aspect of the present invention, there is provided a metal plate provided with a required wiring circuit and a hole by punching a metal plate, and a circuit board provided with a required wiring circuit and a projection provided by punching the metal plate. An insulating substrate is interposed therebetween, and the circuit board is characterized by being integrated by fitting the holes and the protrusions, so that a hole punching step, a plating step, and a soldering step become unnecessary.
Man-hours and costs can be reduced.

According to a sixth aspect of the present invention, at least one of the metal plates is embedded in the insulating substrate such that the surface of the metal plate is substantially flush with the surface of the insulating substrate.
According to the circuit board described above, the integrated strength of the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

According to a seventh aspect of the present invention, a metal plate is formed by punching a metal plate to provide a required wiring circuit and a cylindrical projection, and a metal plate is punched to form a required wiring circuit and a projection. A circuit board, wherein an insulating board is interposed between the circuit board and the tubular projection and the projection are fitted and integrated to form a circuit board; The process becomes unnecessary, and the man-hour and cost can be reduced.

The invention according to claim 8 is characterized in that at least one of the metal plates is embedded in the insulating substrate such that the surface of the metal plate is substantially flush with the surface of the insulating substrate.
According to the circuit board described above, the integrated strength of the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

According to a ninth aspect of the present invention, there is provided a vehicle having a substantially U-shape,
The circuit board according to claim 7, wherein the projection is provided with a hook portion at a tip end, and the number of steps and cost can be reduced.

According to a tenth aspect of the present invention, a metal plate provided with a required wiring circuit and a hole by punching a metal plate and a circuit board provided with a required wiring circuit and a projection provided by punching the metal plate are provided. A circuit board, wherein an insulating substrate is interposed therebetween, and the hole and the end face provided on the projection and the bulging portion are fitted and integrated so as to come into contact with each other at three places. Process, plating process and soldering process become unnecessary,
Man-hours and costs can be reduced.

According to the eleventh aspect of the present invention, the circuit board according to the tenth aspect is characterized in that at least one surface of the metal plate is embedded in the insulating substrate so as to be substantially flush with the surface of the insulating substrate. Thus, the integrated strength of the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

In the twelfth aspect, a metal plate provided with a required wiring circuit and a cylindrical projection by punching a metal plate and a circuit board provided with a required wiring circuit and a projection provided by punching the metal plate are provided. A circuit board, wherein an insulating substrate is interposed, and the hole and the end face provided on the projection and the bulging portion are fitted and integrated so as to come into contact with each other at three places. In addition, the plating step and the soldering step become unnecessary, and the number of steps and cost can be reduced.

According to a thirteenth aspect of the present invention, the circuit board according to the twelfth aspect is characterized in that at least one of the metal plates is embedded in the insulating substrate so that the surface is substantially flush with the surface of the insulating substrate. Thus, the integrated strength of the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

A circuit board according to an embodiment of the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 is an exploded perspective view of the concept of a circuit board according to Embodiment 1 of the present invention, and FIG.
2 shows a perspective view of a cross section of a main part of the conducting portion in FIG.

1 and 2, reference numerals 1A and 1B are metal plates, 2 is an insulating support (insulating substrate), 3A and 3B are through holes, and 4A and 4B are standing around the through holes 3A and 3B. Reference numeral 7 denotes various electronic components mounted on the circuit board, and 100 denotes a circuit board.

The metal plates 1A and 1B are formed by patterning by etching, or by punching a wiring circuit (circuit pattern) as desired by means such as pressing.

Further, the metal plates 1A and 1B are
In order to establish continuity between the wiring circuits when both are disposed on both surfaces of the substrate, through-holes 3A and 3B and cylindrical projections 4A and 4B (for example, cylindrical uprights) around the through-holes are formed in a pressing step. It is drawn. The other projection 4B is fitted (press-fitted) into the hole 3A of the projection 4A.

The surfaces of the metal plates 1A and 1B are embedded in the insulating substrate 2 so as to be substantially the same as the surface of the insulating substrate 2.

Specifically, a hole 3A of a metal plate 1A punched into a required wiring circuit shape and having a protruding portion drawn,
The holes 3B of the metal plate 1B are press-fitted to each other, and then the insulating resin forming the insulating substrate 2 is poured between the metal plate 1A and the metal plate 1B and integrally molded to form the circuit board 10
0 can be produced. That is, any resin member such as epoxy, ABS, PS, or PP is reinforced by means such as insert molding or casting.

As another method of manufacturing the circuit board 100, the metal plates 1A and 1B are laminated such that the prepreg sheet constituting the insulating substrate 2 is sandwiched between the metal plates. The laminate is heated and pressed by a hot press to soften the prepreg sheet. Further, in the process of curing the prepreg sheet, the metal plate 1A is placed in the prepreg base material.
And the metal plate 1B is buried to the vicinity of the surface and the circuit board 10
0 can be formed.

It is to be noted that the cylindrical upright portion (projection 4A) provided on the metal plate 1A may be omitted, and only the hole 3A may be provided.
The metal plates 1A and 1B can be fitted to each other as in the case of FIG.

With the above configuration, the circuit board 100 does not require a hole forming step, a plating step, and a soldering step after lamination, so that the number of steps and cost can be reduced. Further, the integrated strength between the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

(Embodiment 2) FIG. 3 is an exploded perspective view of the concept of a circuit board according to Embodiment 2 of the present invention, and FIG.
2 shows a perspective view of a cross section of a main part of the conducting portion in FIG.

The circuit board 200 in this case is basically the same as that of the first embodiment. The configuration different from the first embodiment is that a cut-and-raised (projection) 34 is provided on one metal plate instead of the protruding portion 4B of FIG.

3 and 4, reference numeral 31B denotes a metal plate,
Numeral 34 denotes a cut and raised portion (projection), and numeral 200 denotes a circuit board.
Other reference numerals and configurations are the same as in the first embodiment.

The cut-and-raised (projection) 34 is formed in a substantially triangular shape having a tapered portion at the tip.
A hole 3A is press-fitted and fitted. Circuit board 200
May be performed in the same manner as in Embodiment 1. The effect is the same.

FIG. 5 is a cross-sectional perspective view of a main part of another circuit board 300 according to the second embodiment. In this case, a projection 54 different from that in FIG. 4 is provided on the metal plate 51B.

That is, the projection 54 is characterized in that it has a slit 55 in the center, is substantially U-shaped, and has a hook at the tip.

When the projection 54 is attached to the hole 3A of the metal plate 1A by this configuration, the hook 56 elastically deforms and bends.
Also, after mounting, it returns elastically and serves as a detent.

Note that the cylindrical upright portion (projection 4A) provided on the metal plate 1A is omitted, and the metal plates 1A and 51B are fitted to each other with only the simple hole 3A as shown in FIGS. Is possible as well.

(Embodiment 3) FIG. 6 is a perspective view of a main part of a metal plate according to a third embodiment of the present invention. FIG. 7 is a perspective view of a cross section of a main part of the metal plate according to the third embodiment of the present invention. Figure 7
Is a cross-sectional view of a relevant part taken along a cutting line SS.

The circuit board in this case is basically the same as that of the second embodiment. The configuration different from the second embodiment is that a protrusion 64 is provided on one metal plate instead of the protrusion 34 of FIG.

6 to 8, reference numeral 61B denotes a metal plate,
Reference numeral 64 denotes a protrusion, 65 denotes a bulging portion, 66 denotes a ridge line portion, 67 denotes a concave portion, 68 denotes an end face, and 400 denotes a circuit board.

The projection 64 has a bulged portion 65 provided at a substantially central portion of the main surface of the bent portion in a mountain shape. When the bulging portion 65 is press-fitted (mounted) into the hole 3A of the metal plate 1A, the hole 3A
Contact at three places on the inner wall.

More specifically, as shown in FIG. 8, when the portion located in the hole 3A was cut in the horizontal direction, the cross-sectional shape was substantially V-shaped.

Further, as shown in FIG. 6, both end faces 68.68 of the insertion portion at least in a region in contact with the inner wall of the hole.
It has a tapered shape with a small width between them and a large width at the base.

Further, in a region where the inner wall of the hole 3A is in pressure contact with the inner wall of the hole 3A, the outer dimension of the insertion portion is larger than the inner diameter of the hole by a predetermined amount.

When the projection 64 configured as described above is press-fitted (mounted) into the hole 3A, the thickness (thickness) of the bulging portion 65 despite the outer shape of the insertion portion is larger than the inner diameter of the hole 3A. However, the recess 67 is easily elastically deformed and contracted because of its small thickness and low rigidity. As a result, the end face 68 and the ridge 66 are closely fitted to the inner wall of the hole 3A.

Note that the cylindrical upright portion (projection 4A) provided on the metal plate 1A is omitted, and the metal plates 1A and 1B can be fitted to each other as in the case of FIG. It is possible.

In the above three embodiments, after the hole or the cylindrical upright portion and the protrusion or the protrusion are fitted (press-fitted) to each other, an adhesive such as epoxy resin or solder is attached to the fitted portion. It is needless to say that such a material may be applied and cured. In addition, it is the same as the above, which is not limited to the press-fitting, but may be a clearance fitting, and may be joined by soldering so as to establish conduction between the metal plates.

According to the above configuration, the circuit board 400 does not require a hole forming step, a plating step, and a soldering step after lamination, so that the number of steps and cost can be reduced. Further, the integrated strength between the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

[0058]

As described above, according to the present invention, holes, plating, and soldering steps after lamination are not required, and the number of steps and cost can be reduced. Further, the integrated strength between the insulating substrate and the metal plate is improved, and smooth mounting of electronic components is enabled.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of the concept of a circuit board according to Embodiment 1 of the present invention.

FIG. 2 is a sectional perspective view of a main part of a conduction unit in FIG. 1;

FIG. 3 is an exploded perspective view of the concept of a circuit board according to Embodiment 2 of the present invention.

4 is a cross-sectional perspective view of a main part of a conduction unit in FIG. 3;

FIG. 5 is a cross-sectional perspective view of a main part of another circuit board according to the second embodiment.

FIG. 6 is a perspective view of a main part of a metal plate according to a third embodiment of the present invention.

FIG. 7 is a sectional perspective view of a main part of a metal plate according to a third embodiment of the present invention.

FIG. 8 is a sectional view of a main part of FIG. 7 taken along a cutting line SS.

FIG. 9 is an exploded perspective view of the concept of a conventional circuit board.

10 is a cross-sectional perspective view of a main part of a conduction unit in FIG. 9;

[Explanation of symbols]

 Reference Signs List 1A, 1B, 31B, 51B, 61B Metal plate 2 Insulating support (insulating substrate) 3A, 3B hole 4A, 4B Projection 4, 34, 54, 64 Cut and protruded (projection) 7 Electronic component 55 Slit 56 Hook 65 Swelling part 67 Depression part 68 End face 100, 200, 300, 400 Circuit board

Claims (13)

[Claims] An insulation is provided between a circuit board provided with a required wiring circuit and a hole by punching a metal plate and a circuit board provided with a required wiring circuit and a cylindrical projection by punching a metal plate. A circuit board, wherein the board and the projection are fitted together to interpose a board therebetween. 2. The circuit board according to claim 1, wherein the surface of at least one metal plate is embedded in the insulating substrate so as to be substantially flush with the surface of the insulating substrate. 3. An insulating substrate is interposed between a circuit board provided with a required wiring circuit and a cylindrical projection by punching a metal plate, and said projections are fitted together to be integrated. A circuit board, comprising: 4. The circuit board according to claim 3, wherein the surface of at least one metal plate is embedded in the insulating substrate so as to be substantially flush with the surface of the insulating substrate. 5. An insulating substrate is interposed between a metal plate punched out of a metal plate and provided with required wiring circuits and holes, and a circuit board punched out of a metal plate and provided with required wiring circuits and projections. A circuit board, wherein the hole and the projection are fitted and integrated. 6. The circuit board according to claim 5, wherein a surface of at least one of the metal plates is embedded in the insulating substrate so as to be substantially flush with a surface of the insulating substrate. 7. Insulation between a metal plate punched out of a metal plate and provided with a required wiring circuit and a cylindrical projection, and a circuit board punched out of the metal plate and provided with a required wiring circuit and a projection. A circuit board, wherein the tubular projection and the projection are fitted and integrated with a board interposed therebetween. 8. The circuit board according to claim 7, wherein the surface of at least one of the metal plates is embedded in the insulating substrate so as to be substantially flush with the surface of the insulating substrate. 9. The circuit board according to claim 7, wherein the projection is substantially U-shaped, and has a projection with a hook at a tip end. 10. An insulating substrate is interposed between a metal plate punched out of a metal plate and provided with required wiring circuits and holes, and a circuit board punched out of a metal plate and provided with required wiring circuits and projections. A circuit board, wherein the hole, the end face provided on the projection, and the bulging portion are fitted and integrated so as to come into contact at three places. 11. The circuit board according to claim 10, wherein the surface of at least one of the metal plates is embedded in the insulating substrate so as to be substantially flush with the surface of the insulating substrate. 12. Insulation is provided between a metal plate punched out of a metal plate and provided with a required wiring circuit and a cylindrical protrusion, and a circuit board punched out of the metal plate and provided with a required wiring circuit and a projection. A circuit board, wherein a board is interposed, and the hole, the end face provided on the projection, and the bulge are fitted and integrated so as to come into contact at three places. 13. The circuit board according to claim 12, wherein a surface of at least one of the metal plates is embedded in the insulating substrate so as to be substantially flush with a surface of the insulating substrate.